多图谱尺度合成和特征的单分散四角形化纳米晶的纳米晶体
Jin Joo1, Taekyung Yu, Young Woon Kim
1Contribution from the National Creative Research Initiative Center for Oxide Nanocrystalline Materials and School of Chemical Engineering, Seoul National University, Seoul 151-744, Korea.
Journal of the American Chemical Society
|June 6, 2003
概括
一种简单的非水解 sol-gel 方法合成了高度单分散的四角形石 nanocrystals. 这一过程产生均的4nm环纳米粒子,具有出色的结晶性和光学性能.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 无机化学 无机化学 有机化学
背景情况:
- (ZrO2) 纳米晶体对各种应用具有独特的特性.
- 控制尺寸,相位和晶度对于优化纳米晶体性能至关重要.
- 现有的合成方法往往缺乏可扩展性或对这些参数的精确控制.
研究的目的:
- 开发一种简单,可扩展的方法,用于合成高度单分散的四角形化纳米晶体.
- 描述合成纳米粒子的结构,晶体和光学特性.
- 为了研究不同前体对纳米粒子大小的影响.
主要方法:
- 在340°C的温度下使用氧化和化的非水解性sol-gel反应.
- 高分辨率传输电子显微镜 (HRTEM) 用于粒子大小和形态分析.
- 用瑞特维尔德精细化进行X射线衍射 (XRD) 用于相位识别和结构分析.
- 紫外线可见吸收,光谱和FTIR用于光学和表面表征.
主要成果:
- 在没有尺寸选择的情况下成功合成了大量高度单分散的4纳米四角 (ZrO2) 纳米晶体.
- HRTEM证实了均的颗粒大小分布和高晶度.
- XRD揭示了高温四角形相,接近立方体.
- 使用二 (IV) 化物产生了2.9nm二纳米粒子.
- 光学研究表明,高质量的纳米粒子具有狭窄的尺寸分布和低表面陷状态.
结论:
- 开发的非水解 sol-gel 方法提供了一种简单有效的途径,以高质量的,单分散四角形石 nanocrystals.
- 合成的纳米粒子具有理想的结构和光学特性,适合先进的应用.
- 该方法通过改变前体来证明纳米颗粒大小的可调性.
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